Refrigerating mechanism



Feb. 2l, 1950 s. MUFFLY Rsmrcm'rmc uzcmmrsu .Filed oct. 9, 194sgmac/who@ Glan??? Muff/q #fall-P.

Patented Feb. 2l, 1950 UNITED STATES PATENT oFFlcE 2,491,903aal-*aroaaamo MacnANlsM Glenn Mumy, spi-mman, ohio Application October9, 1945, Serial No. 521,241

(ci. sz---ln` t l 3 Claims.

This invention relates to refrigerating mechanism and particularly tosuch mechanism as is employed to shift refrigerant now so as to shiftrefrigerating effect from one evaporator to another. This applicationrelates to the same subject matter as my application of October 29, 1938which resulted in U. S. Patent No. 2,359,780 which issued October 10,1944. Reference is made to this issued patent for additional detalls ofthe herein disclosed mechanisms and their uses.

, An object of this invention is to provide a valve mechanism which isactuated by a metering device responsive to the volume of refrigerantvapor flowing through a portion of the system.

Another object is to provide such a valve mechanism with a timedactuating device, the length of the operating period of an evaporatorbeing regulated by the mass of-vapor flowing therefrom.

A further object of this invention is to provide a valve mechanismwithin a refrigerant containlng portion of the system and drivenindependently of any external power source.l

A further object of this invention is to provide a valve timingmechanism which is responsive not only to the time and velocity ofrefrigerant flow but also to variations in the density of refrigerantvapor.

Other objects of the invention will become apparent from the followingspecification, the drawings relating thereto, and the claims hereinafterset forth.

In the drawings in which like numerals are used to designate like partsin the several views throughout: f l

Fig. 1 is a diagrammatic view of a. self-actuating valve mechanismdesigned to act in response to the velocity and density of refrigerantvapor flowing from evaporators.

Fig. 2 is a simplified arrangement of the elements seen inv Fig. 1. f A

Fig. 3 is a sectional view on the line rof Fig. 2.

The assembly seen in Fig. 1 here shown in a somewhat diagrammaticmanner, illustrates the working of Figs. 2 and 3. The actuation of thevalve is obtained independently of the starting and stopping of thecondensing unit, being timed in relation to the density and volumev ofrefrigerant vapor passing to suction tube 59.

As seen in Fig. l the port of tube 61 is open into the gas-tight casing|44, and the gas must pass through orice |45 in the wall |45, whichdivides the casing |44 into two parts in a substantially gas-tightmanner except for this port 2. |45. The Jet of gas striking vanes of thegaswheel |41 produces rotation of this gas-wheel so long as gas is beingremoved through the passage 59 by action of the condensing unit. The fan(gas-wheel) is mounted rigidly upon sleeve |45, which also carriespinion |45. Pinion |49 drives gear |55, which is rigidly connected withpinion |5|. This pinion drives another gear |55 and so on till the lastpinion |5| drives gear |52, which is the same as gears |55 except thatit is mounted on sleeve |53 instead of to Aanother pinion. Sleeve |55carries crank arm |54 on which is mounted the point |55. Shafts |55 and|51 are fitted freely in all of the parts through which they pass,including the cross member |55 in which shaft |55 has a bearing and wall|45 in which shaft |5'lhas a bearing. Sleeves |45 and |55 are free torotate upon their respective shafts as well as in their respectivebearings in wall |45 and cross-member |55, respectively.

The gear ratio and the gas-driven wheel |41 are designed to produce averyslow rotation of sleeve |53 on the order of one revolution per hourfor average running conditions of gas density and velocity in the systemfor which the assembly is designed. The compression spring |55" isfltted with a cupped retainer at each end and held between points |55and |52', thus lbeing in position to hold` the rocker |54' at one or theother of its two extreme positions, closing the port of 55 or 51 as thecase may be. The circular travel of point |55 is onv a radius such thatthe rocker |54 is caused to snap to the opposite position twice in eachfull rotation of sleeve |55. Thus eachof the ports of passages 55 and 51will be open into housing |44 alternately during aportion of arevolution of sleeve |55. As described in my earlier patent applicationabove mentioned, this mechanism may be used to provide an ice-makingperiod and an ice-freeing period for each of the two ice-makerevaporators. In that case the design is .such that the length of anice-freezing period is ample to provide a satisfactory ice-freeingperiod of the same length on the opposite surfaces of the ice-maker.

Figure l is included for the purpose of showing the train of gearingmore clearly than it can be shown in Figs. 2 and 3, which represent muchmore exactly the form of housing and arrangement of parts preferred inpractice.' The gearing seen in Fig. 2 is arranged to perform exactly thesame function as the gears in Fig. 1, as do the gas-wheel |41 and theorifice |45. The dividing wall |55 serves the same function as wall |45of Fig. 1 and in addition is the sole support for the 3 gearingassembly. Wall |66 fits into the lower half |64 of the gas-tight housingand is retained bythe upper half |66 which is gasketed to |64 andsecured together by means of screws and nuts, of which two are shown.

It is not necessary to trace the gearing between gas-wheel |41 andeccentric |61, but the gearing assembly |66 serves to produceapproximately the same rate of eccentric rotation that we had of crank|54 rotation in Fig. 1. This eccentric acts upon the U-shaped arm |68 tomove one end of the spring |06 iirst in one direction and then in theother so that it acts upon the point |62' and the valve rocker |04exactly as before described. The slot in one side of the part |66 isnon-symmetrically formed to produce about the same ratio of movement forsnapping in each direction. The stop |69 attached to part |66 retainsthe arm |68 and prevents spring I from moving it too far in eitherdirection prior to assembly of parts |64 and |65 to each other.

The type of valve mechanism illustratedV by Figs. 1 to 3 inclusive issuitable for use in connection with any type of condensing unit, eitherintermittent or continuous in operation and of either the compression orabsorption type, including adsorption systems and three-fluid systems.It has no external connection with a moving part and exposes no delicatebellows or diaphragm to the refrigerant. The cycling of the evaporatorsis thus independent of the cycling of the condensing unit. It may bedesired to regulate the operation of the condensing unit to stop it whena maximum supplyof ice has'been accumulated or a minimum low temperatureattained but this stopping and starting need not be synchronized withthe cycling of evaporators during one running period. A thermostatic`control may be made subject to cabinet air temperature independently ofevaporator temperature, providing a more uniform cabinet air temperaturecontrol than is possible with any of the conventional thermostaticcontrols.

On account of the very light load on the fastmoving parts and the veryslow motion of the more heavily loaded parts, it is possible to operatethe valve mechanisms with practically no lubrication, but somelubricationis obtained from the refrigerant itself and more from the oilwhich circulates with the refrigerant in most systems. The outlet at 66may be so located that some oil is trapped within the gear housing inposition for one or more of the gears to dip in this oil. Such anarrangement is shown in Fig. 1. Bearings of Figs. 2 and 3 may behardened or jewelled or made of a self-lubricating material such as agraphite-impregnated bronze, or they may be of ball or roller typeswhich will operate under these light loads with no lubrication.

What is claimed is:

1. In a refrigerating system, means forming a refrigerant circuitincluding alternate paths for refrigerant flow, valve means fordiverting refrigerant ow from one to the other of said paths, andmechanical means driven by refrigerant owing through said system foractuating said valve means at timed intervals.

2. In a refrigerating system, means forming an enclosure adapted tocontain a refrigerant, a rotary member driven by the ilow of refrigerantwithin said enclosure, and a control device actuated by said rotarymember at a frequency of operation much lower than the frequency ofrotation of said member.

3. In a refrigerating system, a refrigerant, means forming a ow circuitfor said refrigerant including an enclosure through which saidrefrigerant ilows during operation of said system, a rotary memberwithin said chamber adapted to be driven by the flow of saidrefrigerant, and means actuated by said member to change the path ofsaid refrigerant in its flow through a portion of said system.

GLENN MUFFLY.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,321,230 Miles Nov. 11, 19192,359,780 Muiiiy Oct. 10, 1944 OTHER REFERENCES Double Patenting, byStringham.

